Historically home to the Chumash and Tongva, Los Angeles was claimed by Juan RodrĂguez Cabrillo for Spain in 1542 along with the rest of what would become Alta California. The city was officially founded on September 4, 1781, by Spanish governor Felipe de Neve. It became a part of Mexico in 1821 following the Mexican War of Independence. In 1848, at the end of the Mexican–American War, Los Angeles and the rest of California were purchased as part of the Treaty of Guadalupe Hidalgo, thereby becoming part of the United States. Los Angeles was incorporated as a municipality on April 4, 1850, five months before California achieved statehood. The discovery of oil in the 1890s brought rapid growth to the city.
The completion of the Los Angeles Aqueduct in 1913, delivering water from Eastern California, later assured the city's continued rapid growth.